1. Field of the Invention
The present invention relates generally to protective devices for electrical plugs, and more particularly, to an electrical plug protective device, especially adapted for protecting a plug and a conductor connected to the plug.
2. Description of the Prior Art
When electrical plugs are in good working condition and treated well they provide a reasonable degree of safety from electric shock or short circuiting. However, over time, with extended use, parts of plugs or the conductors connected to the plugs often exhibit signs of wear that may ultimately prove hazardous. More specifically, a connection between a conductor and the backside of a plug is a location where extensive wear may be especially hazardous. As the plug is used over time, the connection between the conductor and the backside of the plug is particularly susceptible to fraying. This is so because this region of the conductor is often subjected to frequent and above normal stresses. When this region of the conductor weakens or frays, the conductor is especially susceptible to short circuiting or breaking. In this respect, it would be desirable if an electrical plug protective device were provided that gave special protection to the region of the conductor that is connected to the backside of the plug.
A number of electrical plug protective devices are disclosed in the prior art. Some of the prior art devices are disclosed in the following U.S. Pat. Nos.: 3,452,321; 3,763,457; 4,305,634; 4,676,570; and 4,944,685. More particularly, U.S. Pat. No. 3,452,321 discloses a protective cover for both male and female connector portions of an electrical connection. One protective structure is associated with the male portion, and a second protective structure is associated with the female portion. When the prongs of a plug are inserted into a wall outlet, the wall and the wall outlet itself provide a degree of protection for the electrical plug connected to the wall outlet. Therefore, under these circumstances, a separate protective portion for the wall outlet is unnecessary. In this respect, it would be desirable if an electrical plug protective device were provided that precluded a separate protective portion for the female connector portion when the male connector portion is connected to the female connector portion.
U. S. Pat. No. 3,763,457 discloses a plug guard for a plug that is not in use. The plug guard in this patent is also used to prevent use of the plug. However, this device cannot be used to protect the plug when the plug is in use in a wall outlet. In this respect, it would be desirable if an electrical plug protective device were provided that can be used on an electrical plug when the plug is connected to a wall outlet.
U.S. Pat. No. 4,305,634 discloses a disk-shaped electrical plug protective device that fits over the prongs of a plug and skews the prongs off center. The disk-shaped device prevents contact of a person's fingers with prongs of the plug when the plug is not fully inserted into the wall outlet. This skewing of the prongs can lead to premature wear and failure of the prongs. In this respect, it would be desirable if an electrical plug protective device were provided which protected an electrical plug without skewing the prongs of the plug.
U.S. Pat. No. 4,944,685 is like U.S. Pat. No. 3,452,321 with respect to a disclosure of a protective cover for both male and female connector portions of an electrical connection. In this respect, the 4,944,685 and the 3,452,321 patents have similar problems.
U.S. Pat. No. 4,676,570 may be of interest for its disclosure of a cover for a wall outlet socket.
Although the prior art described above has the deficiencies described above, the prior art does teach some valuable lessons. The prior art teaches that there are advantages to protecting an electrical plug from damage when it is not in use. There are also advantages in guarding an electrical plug so as to prevent unauthorized use. In this respect, it would be desirable if an electrical plug protective device were provided that also protected an electrical plug from damage when not in use and also prevented unauthorized use. Unauthorized use can be very dangerous, especially when children attempt to use dangerous equipment.
Some of the prior art electrical plug protective devices are difficult to install and may damage the plug during installation. In this respect, it would be desirable if an electrical plug protective device were provided that were easy to install and that did not subject the plug to damage during installation.
Aside from the desirable feature of easy installation, it would also be desirable if an electrical plug protective device were provided that were easy to remove and place on another plug.
Moreover, it would also be desirable if the portion of the protective device that protected the plug from damage when not in use and from unauthorized use could be easily installed or removed from an electrical plug protective device at the option of the user.
An electrical wall outlet generally has a plurality of sockets. Moreover, many times, a multiple socket device will be plugged into a wall socket to expand the number of available sockets. When a plurality of devices are plugged into a plurality of sockets, it is often very confusing as to which plug corresponds to which device. It is often difficult and time consuming to trace conductors back from the wall socket to the particular devices. It may also be very inconvenient to remove plugs one by one, as by trial and error, to identify which plug corresponds to which device. In this respect, it would be desirable if an electrical plug protective device were provided that provided a means for identifying which plug is associated with which device.
In view of the desirable features of an electrical plug protective device mentioned above for a plug that is installed in a wall outlet, it would also be desirable if respective applicable desirable features could also be used with cords having complementary male plugs and female sockets.
Thus, while the foregoing body of prior art indicates it to be well known to use protectors for electrical plugs, the prior art described above does not teach or suggest an electrical plug protective apparatus which has the following combination of desirable features: (1) gives special protection to the region of the conductor that is connected to the backside of the plug; (2) precludes the need for a separate protective portion for the female connector portion when the male connector portion is connected to the female connector portion; (3) can be used on an electrical plug when the plug is connected to a wall outlet; (4) protects an electrical plug without skewing the prongs of the plug; (5) protects an electrical plug from damage when not in use and also prevents unauthorized use; (6) is easy to install and does not subject the plug to damage during installation; (7) is easy to remove from one plug and place on another plug; (8) were provides means for identifying which plug is associated with which device; (9) the portion of the protective device that protects the plug from damage when not in use and from unauthorized use is easily installed or removed from an electrical plug protective device at the option of the user; and (10) can be used with cords having complementary male plugs and female sockets. The foregoing desired characteristics are provided by the unique electrical plug protective apparatus of the present invention as will be made apparent from the following description thereof. Other advantages of the present invention over the prior art also will be rendered evident.